The relationship of Laszlo and Tallulah in the 'Doctor Who' two-parter ("Daleks In Manhattan" & "Evolution Of The Daleks") is one that was even more exciting for me as a televisiologist charting the unknown connections in Toobworld. Laszlo's DNA was combined with that of a pig, with the end result planned for him to become a stronger slave with little mind of his own. But he escaped before the Daleks could mind-swipe him and then later, the Doctor was able to save his life (which originally was only meant to last for a few weeks of hard labor).
I don't think the Doctor bothered to throw in a vasectomy while he was going about saving Laszlo, if he even thought of the consequences of Tallulah giving birth to his children. (And like Brannigan and Valerie inter-breeding in "Gridlock", there'd be a litter of babies in that first pregnancy, no doubt!)
This is why I'm hoping we're back to watching the adventures of 'Doctor Who' set in the main Toobworld, and not the alternate dimension forced on us by the events in "Aliens Of London" and "The Christmas Invasion" (the death of Tony Blair and the installation of Harriet Jones as the Prime Minister, respectively).
Two generations later, Laszlo and Tallulah would have had at least one piglet of a grandchild: Sal the Pig-Boy, who worked as the computer archivist at the Chronicle, a NYC-based tabloid newspaper where all the weird stories about aliens, Bigfoot, and other oddities were actually true.
Perhaps Sal's Dad was the son of Laszlo and Tallulah. It could be that by the late 1990s, he was admitted to a NYC hospital, where he was spotted by Cosmo Kramer. Later, Kramer would change his opinion, and instead opt for the explanation that it wasn't a pig-man but a really ugly guy.
But who knows? Maybe Kramer got it right on the first try.
As to why the reality of a pig-man and his wife and their piggie children leading piggie lives wasn't common knowledge in at least New York City, if not the world, I think the citizens of Hooverville finally took their settlement below ground into the sewer-like caverns beneath the City. There they were free of the hassles from those in authority, and Laszlo and his family would be free of interference by social workers and scientists alike. (This would be the community we would meet decades later in 'Beauty And The Beast'.)
The Doctor exists in the sketch comedy world, as we've seen thanks to Lennie Henry and Rowan Atkinson and Jim Broadbent twice over. So this adventure may have also taken place there as well, but of course with variations due to the dimension.
If so, then the pig-like butchers played by Rick Moranis and Dave Thomas may have also been descendants of Laszlo and Tallulah.
I'm not sure if Clem of 'Buffy the Vampire Slayer' could possibly be related to them..... He was an actual demon, although pretty much a kind-hearted pig demon at that. I think it more likely that he was descended from the union between the demi-god Hercules and a pretty young porkette, as seen in "Porkules", an episode of 'Hercules: The Legendary Journeys'.
I should also add at this point that 'The Chronicle' was a fun TV series, and it deserved a better chance than it got. And I would have loved for a crossover between 'The Chronicle' and 'Eureka', or even with 'The Dresden Files'!
The pig-man! I saw a pig-man! He was just lying there and then he woke up. He looked up at me and made this horrible sound!
Kramer, what the hell are you talking about?
I'm talking about the pigman, George. I went into the wrong room and there he was.
Yes, a pigman. Half pig, half man.